Adjustable footwear sole with bladder

ABSTRACT

An article of footwear includes an upper and a sole secured thereto. The sole includes a midsole with a receptacle, within which a flexible fluid-filled bladder may be fitted. The bladder is adjustable with respect to the midsole between at least first and second orientations. The bladder provides the sole with a first characteristic when in the first orientation and a second characteristic, different from the first characteristic, when in the second orientation. Accordingly, the sole is readily adjustable between the first characteristic and the second characteristic by movement of the bladder with respect to the midsole.

BACKGROUND OF THE INVENTION

The present invention relates to footwear and more particularly tofootwear having a fluid-filled bladder in the sole.

The design and manufacture of footwear is complicated by the fact thatdifferent people have different footwear needs. For example, someindividuals prefer a firmer, more unyielding sole, while others prefer asofter, more cushioning sole. With some people this is simply anaesthetic desire, but for others it can result from physical factors,such as those associated with foot shape, skeletal alignment and otheranatomical issues. Anatomical issues cause some individuals to sufferfrom a tendency to pronate (roll their feet inward when striding) andothers to have the opposite tendency to supinate (roll their feetoutward when striding). One method for addressing these issues is tostiffen the sole in select regions to provide increased resistanceagainst the undesired motion. For example, pronation can be addressed byproviding a dual-density midsole with a higher density region along themedial side of the sole. Similarly, supination can be addressed byproviding a dual-density midsole with a higher density region along thelateral side of the sole.

Additionally, some footwear products include cushioning inserts whichmay be in the form of resilient pads or fluid filled bladders. Many ofthe conventional fluid filled bladders have been filled with a gas, suchas air, while others have been filled with liquids or viscous gel. Thesefluid filled bladders may be manufactured in several ways, includingwelding two layers of elastomeric film together. The bladder is thenpressurized by inserting a nozzle or needle, which is connected to afluid pressure source, into a fill inlet formed in the bladder. Afterthe bladder is pressurized, the nozzle is removed and the fill inlet issealed, for example by welding.

SUMMARY OF THE INVENTION

The present invention provides an article of footwear having an upperand a sole secured to the upper. The sole includes a midsole with areceptacle, within which a flexible fluid-filled bladder may be fitted.The bladder is adjustable with respect to the midsole between at leastfirst and second orientations. The bladder provides the sole with firstcharacteristics when in the first orientation and secondcharacteristics, different from the first characteristics, when in thesecond orientation. Accordingly, the sole is readily adjustable betweenthe first characteristics and the second characteristics by movement ofthe bladder with respect to the midsole.

In one embodiment, a sole for an article of footwear includes a midsolewith at least one receptacle and an adjustable, fluid-filled bladderfitted within the receptacle. The bladder is adapted to fit into thereceptacle in a plurality of orientations so as to provide the sole withdifferent characteristics. Further, adjustment of the characteristics ofthe sole may be achieved by selectively fitting the bladder into thereceptacle in a desired one of the plurality of orientations.

In yet another embodiment, an article of footwear includes an upper anda sole secured to the upper. The sole includes a midsole and a flexiblefluid-filled bladder fitted within the midsole. The bladder has asubstantially vertical axis and is adjustable with respect to themidsole between at least first and second orientations. The bladderprovides the sole with first characteristics when in the firstorientation and second characteristics, different from the firstcharacteristics, when in the second orientation. Further, the midsoleincludes a receptacle for engagement with the bladder, the receptaclehaving an interface surface with a plurality of projections. The bladderalso includes an interface surface with a plurality of projectionsmatingly engaged with the plurality of projections on the receptacleinterface surface. The bladder defines at least two discrete fluidchambers, and the bladder is movable with respect to the receptaclebetween at least a supination orientation to address problems associatedwith supination, a pronation orientation to address problems associatedwith pronation, a regular orientation, and a firm orientation.

These and other objects, advantages, and features of the invention willbe readily understood and appreciated by reference to the detaileddescription of the current embodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a mid-line cross sectional view of an article of footwearaccording to one embodiment of the present invention;

FIG. 2 is mid-line cross sectional view of a midsole and bladder of thearticle of footwear shown in FIG. 1;

FIG. 3 is a top plan view of the midsole;

FIG. 4 is a top plan view of the midsole and installed bladder;

FIG. 5 is a detailed, top isometric view of a receptacle of the midsole;

FIG. 6 is a side elevational view of a portion of the midsole andinstalled bladder;

FIG. 7 is a top isometric view of the bladder;

FIG. 8 is a bottom isometric view of the bladder;

FIG. 9 is a cross-sectional view of the bladder, taken along line IX-IXof FIG. 8;

FIG. 10 is a cross-sectional view of the bladder, taken along line X-Xof FIG. 8;

FIG. 11 is a schematic view of the bladder;

FIG. 12 is a schematic view of the bladder, illustrating the flow offluid within chambers of the bladder during a heel strike;

FIG. 13 is a cross-sectional view of the midsole and bladder, takenalong line XIII-XIII of FIG. 4;

FIG. 14 is a cross-sectional view of the midsole and bladder, takenalong line XIII-XIII of FIG. 4, illustrating the flow of fluid withinthe chambers of the bladder during a heel strike;

FIG. 15 is a mid-line cross sectional view of an article of footwearaccording to another embodiment of the present invention; and

FIG. 16 is mid-line cross sectional view of a midsole and bladder of thearticle of footwear shown in FIG. 15.

DESCRIPTION OF THE CURRENT EMBODIMENT

An article of footwear in accordance with an embodiment of the presentinvention is shown in FIGS. 1-16 and generally designated 9. Theillustrated embodiment of the article of footwear 9 generally includes afootwear sole 10, an upper 11 to which the sole 10 is secured, and anoutsole 16 which may also include a heel wedge (not shown). The sole 10includes a midsole 12 and a flexible fluid-filled bladder 14. Themidsole 12 includes a receptacle 18 adapted to receive the bladder 14.

The sole 10 may be seated within essentially any article of footwear.For purposes of disclosure, the present invention is described inconnection with a midsole construction. The present invention may,however, be integrated into other midsoles, such as an outsole, aninsole or a heel wedge. In a midsole construction, the sole is typicallydisposed above or seated within a void in the outsole. Further, thepresent invention is described in connection with a bladder positionedin the heel region. A bladder may alternatively or additionally bepositioned in other regions of the sole, such as under the forefoot orother locations where the type of adjustability provided by thisconstruction may be desirable.

The present invention is primarily described in connection with a sole10 configured to be incorporated into a left shoe 9. The sole for theright shoe may be a mirror image of the described left sole 10.Accordingly, the right bladder may be a mirror image of the left bladder14.

Referring to FIGS. 1-6, the midsole 12 provides the main cushioning bodyof the sole 10. The midsole 12 of this embodiment is a full-lengthmidsole that follows the general shape of an article of footwear and isconfigured to be fitted into the upper 11 above the outsole 16 or otherunderlying sole component. The midsole 12 of this embodiment is a singleunitary construction that is essentially coextensive with the outsole16, however, the midsole may be a collection of separate components ormay be a partial midsole configured to extend through only one or moreselect portions of the sole. Referring again to the illustratedembodiment, the midsole 12 includes a forefoot region 30, an arch region32, and a heel region 34. The forefoot region 30 is configured tosupport the wearer's forefoot. The arch region 32 may be shaped toprovide an arch support. The heel region 34 includes the receptacle 18,which is configured to receive the bladder 14. Although this embodimentshows a single receptacle 18 in the heel region 34, the receptacle 18may be located in other positions, such as in the forefoot region 30,and the midsole 12 may define a plurality of receptacles 18 configuredto receive a plurality of bladders 14. For example, separate bladders 14may be located in the heel region 34 and in the forefoot region 30 toprovide adjustability in both areas of the sole 10. In the illustratedembodiment, the receptacle 18 is a generally disc-shaped void into whichthe bladder 14 may simply be inserted.

The receptacle 18 has a top surface 20, also referred to as an interfacesurface, which may include a plurality of projections or lobes 26. Thelobes 26 may be positioned on the top surface 20 in a pattern of regularwaves coinciding with angular sections of the receptacle 18. In theillustrated embodiment, the receptacle 18 includes eight lobes 26arranged in a regular repeating pattern about the center of the topsurface 20; however, more or fewer lobes 26 are also contemplated.Although the lobes 26 of the illustrated embodiment are formed by smoothand continuous curved contours, the term “lobes” is used broadly torefer to essentially any contours, whether or not such contours arecurved, smooth or run continuously together. The top surface 20 of thereceptacle 18 may also include a support layer (not shown), such as athin layer of TPU or a harder EVA. The size, shape and configuration ofthe optional support layer may be varied from application to applicationto provide the desired level of cushion/support while maintainingstructural integrity. Additionally, the article of footwear 9 may alsoinclude an optional sock liner 44 (FIG. 1). The design and configurationof the sock liner 44 may vary from application to application.

The midsole 12 may be manufactured from essentially any suitablematerial or combination of materials capable of providing the desiredcushioning/support characteristics. The hardness of the midsole 12 mayvary from application to application as desired. The midsole 12 may bemanufactured using essentially conventional molding techniques andapparatus. The midsole 12 may be injection molded as a single integralunit in which the receptacle 18 is formed during the molding process.The midsole 12 may alternatively be pre-manufactured (e.g. pre-molded)and then die cut or otherwise processed to form the receptacle 18. Themidsole 12 may alternatively be manufactured from a plurality ofmultiple components, for example, with separate heel and forefootportions. The separate components may be combined during manufacture,such as by compression molding or through the use of adhesives.

Referring now to FIGS. 7-10, the bladder 14 is a generally disc-shapedmember that has a substantially vertical axis 58 and that defines atleast two discrete fluid chambers. In the illustrated embodiment, thebladder 14 includes a first chamber 50 and a second chamber 52. Thebladder 14 may also include a center chamber 54. In the illustratedembodiment, the center chamber 54 is circular and is located at thecenter of the circular bladder 14. The first and second chambers 50, 52are substantially semi-circular and encircle the center chamber 54. Thefirst and second chambers 50, 52 are shown being substantiallyequivalent in size and proportion; however, it is contemplated that thesplit between the first and second chambers 50, 52 may be unequal; a60/40 split, for example. Other geometries for the chambers 50-54 arealso feasible; for example, a square center chamber 54 surrounded bymirror image first and second chambers 50, 52.

According to an embodiment, the pressure of the fluid within thediscrete chambers 50, 52 may be different relative to one another,thereby providing differing pressure distributions to the wearer's heeldepending on the orientation of the bladder 14. For example, the fluidpressure within the first chamber 50 may be provided at a predeterminedfirst pressure P1, and the fluid pressure within the second chamber 52may be provided at a predetermined second pressure P2 that is higherthan the first pressure P1. The different pressures P1, P2 within thechambers 50, 52 provide different support and cushioning characteristicsto the sole 10. Additionally, the center chamber 54 may be fluidlycommunicable with one of the first and second chambers 50, 52. In theillustrated embodiment, the center chamber 54 is fluidly communicablewith the second chamber 52, and the pressure in the center chamber 54 istherefore equal to the second pressure P2 of the second chamber 52.Schematics of the bladder 14, depicting the chambers 50-54, are shown inFIGS. 11 and 12. Although not shown, alternately, the center chamber 54may be fluidly communicable with the first chamber 50 and have apressure equal to the first pressure P1 of the first chamber 50.Further, the chambers 50-54 may be filled with air, Nitrogen gas, water,or any other suitable liquid, gas, or viscous gel. Exemplary values forthe pressures P1 and P2 are 9 psi and 12 psi; these values are forexemplary purposes only, and are not to be considered so limiting.

Referring to FIG. 6, the fluid-filled bladder 14 is configured to beremovably seated within the receptacle 18. The bladder 14 has a bottomsurface 22, also referred to as an interface surface, which includes theplurality of projections or lobes 24 configured to be interfitted withand to matingly engage the lobes 26 of the receptacle 18. One or more ofthe lobes 24, 26 may vary in size, shape, resiliency, rigidity or othercharacteristic from the remainder of the lobes 24, 26. For example, thelobes 24, 26 may vary in height. Other alternative geometries,configurations and characteristics are disclosed in co-owned U.S. Pat.No. 7,950,168, entitled “Adjustable Footwear Sole Construction,” U.S.Pat. No. 7,950,167, entitled “Adjustable Footwear Sole Construction,”and U.S. patent application Ser. No. 12/496,177, entitled “SoleConstruction and Related Method of Manufacture,” the disclosures ofwhich are hereby incorporated by reference in their entirety.Additionally, the lobes 24, 26 may be formed of any suitableundulations, ridges, and lobes.

The bladder 14 is adapted to removably fit into the receptacle 18 in aplurality of orientations to provide the sole 10 with differentcharacteristics. The orientation of the bladder 14 is adjustable withrespect to the midsole 12 (and receptacle 18) by rotation about the axis58. Rotating the bladder 14 causes repositioning of both the lobes 24and the first and second chambers 50, 52, which results in variation ofthe support/cushioning characteristics of the sole 10. For example, thebladder 14 is selectively adjustable with respect to the midsole 12between first and second orientations. The bladder 14 provides the sole10 with first characteristics when in a first orientation A, andprovides the sole 10 with second characteristics, different from thefirst characteristics, when in the second orientation B. Accordingly,the sole 10 is readily adjustable between the first and secondcharacteristics by movement of the bladder 14 with respect to themidsole 12. Further, it should be easily understood that the bladder 14may be selectively fitted into the receptacle 18 in any one of thedesired plurality of orientations, and is not limited to just the firstand second orientations A and B.

The bladder 14 is movable with respect to the receptacle 18 between atleast a supination orientation and a pronation orientation. Supinationis described as the tendency to roll one's feet outward when striding,while pronation is described as the tendency roll one's feet inward whenstriding. To correct for these issues, the sole 10 can be stiffened inselect regions to provide increased resistance against the undesiredmotion. For example, pronation can be addressed by orienting the bladder14 to have the higher pressure second chamber 52 disposed on the medialside of the sole 10. Similarly, supination can be addressed by orientingthe bladder 14 to have the higher pressure second chamber 52 disposed onthe lateral side of the sole 10. During a stride, the center of thewearer's heel first strikes the center chamber 54, compressing thecenter chamber 54 and pushing at least a portion of the fluid into theconnected second chamber 52. This, of course, increases the pressurewithin the second chamber 52. During a stride, the difference betweenthe pressures P1 and P2 within the first and second chambers 50, 52becomes greater, further enhancing the corrective ability of the bladder14. FIGS. 13 and 14 show the sole 10 installed in a left article offootwear. In this illustration, the bladder 14 is installed in the“supination” orientation and the inflation of the second chamber 52 isexaggerated for illustrative purposes. Rotating the bladder 14 such thatthe second chamber 52 is disposed on the medial side of the sole 10positions the bladder 14 in the “pronation” orientation.

The bladder 14 and the receptacle 18 may also include an alignment meansfor aligning the bladder 14 within the receptacle 18 in one of theplurality of orientations. In one embodiment, the bladder 14 andreceptacle 18 may be shaped such that the bladder 14 fits into thereceptacle 18 only in select orientations. For example, one of thebladder 14 and the receptacle 18 may include a key (not shown) and theother may include a plurality of slots that receive the key only whenthe bladder 14 is in one of the permissible orientations.

Referring back to FIG. 4, the midsole 12 and bladder 14 may includegraphics, printed material or other symbols that assist in aligning thebladder 14. For example, the midsole 12 may be provided with analignment indicator 60 (in this case, an arrow) and the bladder 14 maybe provided with a plurality of similar alignment indicators 62 (in thiscase, a plurality of arrows) that show permissible orientations of thebladder 14. The bladder 14 may also include text or symbols that work inconjunction with the alignment indicators 60 and 62 to provide a visualindication of the results of the bladder 14 orientation. For example,the words “PRONATION,” “SUPINATION,” “REGULAR,” and “FIRM” may beprinted on the insert adjacent to the appropriate alignment indicators62.

Additionally, the center chamber 54 may be shallower than the first andsecond chambers 50, 52 and may be adapted to be fitted over a centralpost 36 located in the receptacle 18. The recessed center chamber 54 andcentral post 36 may help to assist in aligning and/or retaining thebladder 14 in the receptacle 18. The central post 36 may, however, beeliminated in favor of other configurations.

The sole 10 of FIGS. 1-14 is configured so that the bladder 14 isaccessible from a top surface of the midsole 12, the bladder 14 beingoriented atop the midsole 12. Thus, the midsole 12 and bladder 14assembly may be removably fitted into an article of footwear, forexample, by dropping the midsole 12 and bladder 14 assembly through thefoot opening into the upper 11 and positioning it above the outsole 16.Referring now to FIGS. 15 and 16, alternatively, the midsole 12′ andbladder 14′ assembly may be oriented in the opposite position, with thebladder 14′ mounted to an underside of the midsole 12′.

The present invention may be incorporated into essentially any type offootwear, including but not limited to shoes, boots, sandals, slippersand athletic wear. Further, the present invention may be incorporatedinto essentially any footwear construction. For example, the soleconstruction may be incorporated into direct attach, welt, cement,stroble, California, opanka, lasted, slip lasted and other footwearconstructions. The entire sole construction may be removably fitted intoa void in an outsole, midsole or other sole component. Alternatively,select components of the present invention, such as the midsole and heelwedge, may be secured to the remainder of the sole. If an optional sockliner is included in the construction, it will typically be removable ifits removal is necessary to provide access to the bladder.

The above description is that of the current embodiment of theinvention. Various alterations and changes can be made without departingfrom the spirit and broader aspects of the invention as defined in theappended claims, which are to be interpreted in accordance with theprinciples of patent law including the doctrine of equivalents. Anyreference to claim elements in the singular, for example, using thearticles “a,” “an,” “the” or “said,” is not to be construed as limitingthe element to the singular.

1. An article of footwear comprising: an upper; and a sole secured tothe upper, the sole including a midsole having a receptacle and aflexible fluid-filled bladder fitted within the receptacle, the bladderbeing adjustable with respect to the midsole between at least first andsecond orientations, the bladder providing the sole with a firstcharacteristic when in the first orientation, the bladder providing thesole with a second characteristic different from the firstcharacteristic when in the second orientation, whereby the sole isreadily adjustable between the first characteristic and the secondcharacteristic by movement of the bladder with respect to the midsole.2. The article of footwear of claim 1, wherein the bladder defines atleast two discrete fluid chambers.
 3. The article of footwear of claim2, wherein the bladder includes a high pressure chamber and a lowpressure chamber.
 4. The article of footwear of claim 3, wherein thebladder further comprises a center chamber.
 5. The article of footwearof claim 2, wherein the bladder is generally disc shaped and includes asubstantially vertical axis, the bladder being movable between the firstorientation and the second orientation by rotation about the axis. 6.The article of footwear of claim 5, wherein the receptacle includes aninterface surface and the bladder includes an interface surface, whereinat least one of the receptacle interface surface and the bladderinterface surface has projections extending therefrom for engaging theother of the receptacle interface surface and the bladder interfacesurface, wherein variations in the projections provide the sole withdifference characteristics.
 7. The article of footwear of claim 6,wherein the bladder interface surface has projections matingly engagingthe projections on the receptacle interface surface.
 8. The article offootwear of claim 7, wherein the projections on the bladder and on thereceptacle are selected from the group consisting of undulations,ridges, and lobes.
 9. The article of footwear of claim 4, wherein thechambers are filled with one of a gas, liquid, and a viscous gel.
 10. Asole for an article of footwear comprising: a midsole including areceptacle; and a fluid-filled bladder received within the receptacle,wherein the bladder is adapted to be rotatably received within thereceptacle in a plurality of orientations to provide a wearer's heelwith a corresponding plurality of pressure distributions, wherebyadjustment of a pressure distribution may be achieved by selectivelyfitting the bladder into the receptacle in a desired one of theplurality of orientations.
 11. The sole of claim 10 wherein at least oneof the plurality of pressure distributions is asymmetrical with respectto a midsole longitudinal centerline to correct one of pronation andsupination in the wearer's step.
 12. The sole of claim 10, wherein thefluid-filled bladder includes a center chamber and first and secondperipheral chambers.
 13. The sole of claim 12, wherein the firstperipheral chamber includes a fluid at a first pressure and wherein thesecond peripheral chamber includes a fluid at second pressure differentfrom the first pressure.
 14. The sole of claim 12, wherein the centerchamber is fluidly communicable with only one of the first and secondperipheral chambers.
 15. The sole of claim 10, wherein the receptacleincludes an interface surface and wherein the bladder includes aninterface surface, wherein at least one of the receptacle interfacesurface and the bladder interface surface includes projections extendingtherefrom for engaging the other of the receptacle interface surface andthe bladder interface surface.
 16. The sole of claim 10, wherein thereceptacle further includes alignment indicator for aligning the bladderwithin the receptacle in one of the plurality of orientations.
 17. Anarticle of footwear comprising: an upper; and a sole secured to theupper, the sole including a midsole and a flexible fluid-filled bladderfitted within the midsole, the bladder having a substantially verticalaxis and being adjustable with respect to the midsole between at leastfirst and second orientations, the bladder providing the sole with firstcharacteristics when in the first orientation and secondcharacteristics, different from the first characteristics, when in thesecond orientation; wherein the midsole includes a receptacle forengagement with the bladder, the receptacle includes an interfacesurface with a plurality of projections, and the bladder includes aninterface surface with a plurality of projections matingly engaged withthe plurality of projections on the receptacle interface surface;wherein the bladder defines at least two discrete fluid chambers, andthe bladder is movable with respect to the receptacle between at least asupination orientation to address problems associated with supination, apronation orientation to address problems associated with pronation, aregular orientation, and a firm orientation.
 18. The article of footwearof claim 17, wherein the bladder includes a first chamber containingfluid at a first pressure and a second chamber containing fluid at asecond pressure that is higher than the first pressure.
 19. The articleof footwear of claim 18, wherein the bladder further comprises a centerchamber.
 20. The article of footwear of claim 19, wherein the centerchamber is fluidly communicable with the second chamber.
 21. Afluid-filled bladder for use with a footwear component comprising: adisc-shaped member being rotatable with respect to the footwearcomponent, the disc-shaped member including first and secondfluid-filled chambers, the first and second fluid-filled chambers beingisolated from each other to define a first fluid pressure and a secondfluid pressure, respectively, wherein the first fluid pressure isdifferent from the second fluid pressure to provide a pressuredistribution that varies with rotation of the disc-shaped memberrelative to the footwear component.
 22. The fluid-filled bladder ofclaim 21 further including a central chamber interposed between thefirst and second chambers.
 23. The fluid-filled bladder of claim 22wherein the first and second chambers are semi-circular and arepositioned radially outward of the central chamber.
 24. The fluid-filledbladder of claim 22 wherein the central chamber is in fluidcommunication with the first chamber and isolated from the secondchamber.
 25. The fluid-filled bladder of claim 21 wherein the first andsecond chambers define a plurality of projections extending therefrom.26. The fluid-filled bladder of claim 21 wherein the footwear componentincludes one of an insole, a midsole, and an outsole.
 27. A footwearconstruction comprising: a footwear component; and a fluid-filledbladder adapted to interfit with the footwear component, thefluid-filled bladder including first and second fluid-filled chambers,wherein the fluid-filled bladder is rotatable with respect to thefootwear component between a first orientation and a second orientationto provide a first pressure distribution and a second pressuredistribution, respectively.
 28. The footwear construction of claim 29wherein the footwear component includes one of an insole, a midsole, andan outsole.
 29. The footwear construction of claim 27 wherein thefluid-filled bladder is generally disc shaped and includes a pluralityof projections.
 30. The footwear construction of claim 27, wherein thefirst and second fluid-filled chambers are filled with one of a gas, aliquid, and a viscous gel.